PortablePrism.Portable by Andrii Chebukin

<PackageReference Include="PortablePrism.Portable" Version="1.0.1" />

 ErrorsContainer<T>

public class ErrorsContainer<T>
Manages validation errors for an object, notifying when the error state changes.
public bool HasErrors { get; }

Gets a value indicating whether the object has validation errors.

public ErrorsContainer(Action<string> raiseErrorsChanged)

Initializes a new instance of the ErrorsContainer<T> class.

public void ClearErrors<TProperty>(Expression<Func<TProperty>> propertyExpression)

Clears the errors for the property indicated by the property expression.

public void ClearErrors(string propertyName)

Clears the errors for a property.

public IEnumerable<T> GetErrors(string propertyName)

Gets the validation errors for a specified property.

public void SetErrors<TProperty>(Expression<Func<TProperty>> propertyExpression, IEnumerable<T> propertyErrors)

Sets the validation errors for the specified property.

public void SetErrors(string propertyName, IEnumerable<T> newValidationResults)

Sets the validation errors for the specified property.